The U.S. Food and Drug Administration (FDA) recently reported a possible link between breast implants and a very rare form of lymphoma -- anaplastic large-cell lymphoma (ALCL) -- in tissue near the implant. Lymphoma is cancer in the lymphatic system.

Most women who have mastectomy to treat breast cancer go on to have one or both breasts reconstructed. There are two main ways to reconstruct a breast:

using tissue transplanted from another part of your body (such as your back, belly, or thighs)

inserting an implant that's filled with salt water (saline), silicone gel, or a combination of the two

Saline implants are the most common implant used. A saline implant has a silicone shell that is filled with saline. Silicone gel implants are filled with liquid or firm silicone gel. They tend to feel softer than saline implants and some women think the texture is more like natural breast tissue.

Doctors estimate that ALCL is diagnosed in one of every 500,000 women, making it extraordinarily uncommon. ALCL can develop in other places in the body besides the breast. A diagnosis of ALCL in the breast is extraordinarily rare: among 100 million women, experts estimate that only three cases would be diagnosed in a year.

The possible link between breast implants and ALCL came to light when a study identified 34 women diagnosed with ALCL in a breast with an implant. Because ALCL is incredibly rare, the researchers doing the study and the FDA took notice when 34 women were diagnosed with breast ALCL; both groups began to think there could be a link between breast implants and breast ALCL. FDA scientists looked at results from other studies, consulted implant experts and manufacturers, and contacted international health agencies. The scientists identified six more U.S. women and about 24 international women who were diagnosed with breast ALCL in a breast with an implant. Most of the women with breast ALCL had a breast implant to enlarge the breast, not as reconstruction after breast cancer surgery.

Once a breast implant is in place, scar tissue forms around it, creating what's called a tissue capsule. The FDA found that breast ALCL usually developed in and around the tissue capsule. Breast ALCL was found around both silicone and saline implants, though more cases of ALCL were in women with silicone implants.

Most of the women went to their doctors and were diagnosed with breast ALCL because fluid had collected around the implant (called a seroma) YEARS after the implant was placed. In some cases, testing the seroma fluid led to the diagnosis. (Seromas often develop a week or so after breast implant surgery when the drainage tubes have been removed.) In other cases, ALCL was diagnosed after a mass was found in the breast or because the tissue capsule tightened (called capsular contracture) and caused discomfort or cosmetic problems.

The link between implants and rare breast ALCL hasn't been confirmed. So the FDA is asking for help investigating the link and determining how large the risk is. The FDA is:

asking doctors to consider a possible ALCL diagnosis if a woman with a breast implant placed years ago develops unexplained fluid around the implant that doesn't resolve in a timely way. In these cases the FDA recommends a fluid sample be collected and sent to a pathologist who can look for ALCL.

asking doctors to report any women who have a confirmed diagnosis of breast ALCL

registering all women who have implant surgery in a special database to track how they do over time

asking implant manufacturers to help monitoring efforts

It's very important to know that the FDA ISN'T SURE that a link exists between breast implants and breast ALCL. The FDA emphasized that even if there is a link, the risk of breast ALCL in women with breast implants is still extremely low. Currently available FDA-approved breast implants are safe when used as recommended by the manufacturer. The FDA advised "women with breast implants who are not showing any symptoms or problems, such as pain, lumps, swelling, or asymmetry, require only routine follow-up."

If you have a breast implant, be reassured by the FDA's advice for women and their doctors about implants. Still, don't hesitate to call your doctor if you're still concerned. Definitely call your doctor if you have symptoms or problems with your implant, such as pain, lumps, swelling, or asymmetry.

If you've been diagnosed with breast cancer and are considering reconstruction with an implant, you might want to discuss the FDA announcement with your doctor. Still, know that the FDA doesn't think that the possible link between implants and rare breast ALCL should discourage women from implant reconstruction.

Visit the Breastcancer.org Breast Reconstruction section to learn more about breast implant surgery and other breast reconstruction options.